The different levels of compressed cobble can be finicky. As suggested earlier in the thread, best bet, and what I did, was to give myself a sample set of a few of each tier of compression until I found a reliable decomp, (meaning it runs it, NOT that it yields something), my pc, build, etc, lets me do quad but nothing higher. Still, all it takes is 1 quad cobble to hit and your literally running to keep up with all the output. It drops off a bit as you drop down towards single compression, but even a double compressed cobble yields a pretty big pay day, just make sure you have a few to run, a stack is best, and be ready for all those chems!
Out of curiosity, and off of the iron thing..., any1 mess around with electric age, the modular pack, or, dare I go there, open computers? For open computers and electric age, I really like the idea of having computers, cabling, and wires dotted around as that seems to add a lot of character and authenticity. Can almost smell the ozone and see the sparks. Those 2 mods in particular though seem really advanced. (like writing code! yikes!) Still, I haven't seen a lot of discussion on them and they seem really cool and probably useful. I will probably mess around with them a bit soon, already collecting resin on a new observatory game.